Measuring mercury into fluorescent lamps



Feb. 23, 1943- Q CHlRELsTElN 2,311Q930 MEASURING MERCURY INT0FLUORESCENTLAMPS Filed July 12, 1941v zazles zelsl'ezh,

zNvEm-OR.

'TTRNW Patented Feb. 23, 1943 UNITED STATES PATENT oFFicE MEASURINGMERCURY INTO FLUORESCENT LAIMPS Charles Chirelstein, Newark, N. J.

Application July 12, 1941, Serial No. 402,089

Claims.y

The invention here disclosed relates to the` furnishing of fluorescentlamps and the like with measured quantities of mercury.

Objects of the invention are to provide a prac tical method and meansfor accurately supplying the requisite small quantities of mercuryemployed in fluorescent lamps and the like, and which will work inreadily with existing equi-pment now used in the manufacture of suchdevices.l

Other objects and purposes of the invention will appear as thespecification proceeds.

The drawing accompanying and forming part of the following specificationillustrates one prac'- tical commercial embodiment of the' invention,but it is realized that changes and modifications may be made all withinthe true intent and broad scope of the invention as hereinafter definedand claimed.

Fig 1 is a-schematic end view of one form of apparatus suited to thepractice of the invention.

Fig. 2 is a .broken front view of the same.

Fig. 3 is a wiring diagram and part detail view.

In the several views, a fluorescent lamp tube is indicated at 5, inprocess oi' evacuation, temv porarily connected by tubing 6, with amanifold 1, connected at 8, 9, with a mercury vapor pump l0, and oilpump II.

A mercury well or reservoir I2, is shown connectedby a branch I3, withthe lamp evacuating tube 6, there being in practice one such mercurywell for each evacuating tube. These wells may have filling nipples suchas indicated at I4.

y Mercury in the wells I2 is distilled off lby surrounding or enclosinghigh frequency heating coils I5 and the so purified vapors are drawn offby the evacuating means 9, Ill, through the branches I3, into theevacuating tubes 6. The branches I3 lead out of the tops of the 'wellsI2 and are shown in Fig. 1 inclined downwardly into the tubes Ii, whichopen into the tops of the lamp tubes. The heavier mercury vapors arethus in effect trapped and dropped down into the lam-pl tubes, theapplied suction being regulated and the action timed to effect thisresult.

The high frequency coils may be carried by supports I6, which may beraised to enclose and Ylowered from about the wells, by hand, or bymechanism, automatic or controlled. Alternatively the coils may remainin Iplace about the wells and control be effected wholly by the circuit.

In the diagram, Fig. 3, a timer I'I, is shown in the power circuit I8,governing a magnetic or are required for each lamp, the wells may beswitch I9 for the high frequency furnace 20. which supplies the energyto the high frequency coils I5.

In Fig. 3 there is also shown Aan enclosed capillary 2l for dischargingand trapping the distilled mercury vapor into the lamp tube.

Ina present preferred method of operation the high frequency coils areraised by hand about the mercury stills as evacuation and degasiflcationare completed, as indicated by appearance of the tubes and held therewhile .with the almost immediate boiling of the mercury, the requiredamount or number of drops of mercury is or are observed, condensing anddropping intothe lamp tube. Very accurate results are obtainable in thismanner and a certain latitude of judgment may be observed, thus to admitonly a slight or a greater amount of the distilled, purified, mer-CIJ-ry.

The use of the timer may be desirable for more continuous, rapid anduniform high production, economical manufacture, in which case, thecoil, or the coils, in the event of a multiple tube machine, such asshow-n, :may remain in place and the timer be thrown in, each time atube or tubes is or are ready for the mercury.

As only one or only a few drops of mercury is quite small and this inturn means that the distillation and transfer of mercury vapors to thelamp envelope is quick and positive.

What is claimed is: v

1. 'I'he method of supplying a small quantity of purified mercury to afluorescent lamp in course of manufacture, which comprises connecting aconfined body of mercury into the ex.- haust system by which the tube ofthe lamp is evacuated and surrounding said confined body with a highfrequency and passing high frequency electric current through said coilwhile the tube is undergoing evacuation and for a time suflicient todistill off mercury vapors from said conned body into said tube to theamount desired in the lamp.

2. 'I'he method of supplying a small quantity of purified mercury to afluorescent lamp in course of manufacture, which comprises connecting -aconiined body of mercury through a capillary passage into the exhaustsystem by which the tube of the lamp is evacuated and subjecting saidconfined'body to high frequency electric current while the tube isundergoing evacuation and for a time suflicient to distill oil mercuryvapors from said confined body into said tube to the amount desired inthe lamp.

3. The method of supplying a measured quantity of puried mercury in avaporous'state to an evacuated lamp in course of manufacture and whichcomprises connecting a confined body of liquid mercury -with the tube bywhich the lamp envelope is evacuated and while the envelope is in courseof evacuation and surrounding said conlined body of mercury with a highfrequency electric eld for a time suflcient to distill off an amount ofmercury vapor sufficient for that required in the lamp and whereby suchmeasured volume of mercury vapors will be transported by the evacuation,from the'region of the confined body of liquid mercury into the envelopeof the lamp being evacuated.

4. Apparatus for supplying measured quantities of mercury to fluorescentlamps, comprising in combination with a lamp evacuating tube, a mercurywell for conning and holding a body of liquid mercury connected at thetop with the side of said tube, a high frequency coil for heat'- ing anddlstilling the mercury in said well and means for enabling regulation ofsuch distillation, including a support for locating and holding saidhigh frequency coil in surrounding relation about said mercury well.

5. \Apparatus for supplying measured quantities of mercury vaportoiluorescent lamps, comprising in combination with a lamp evacuatingtube, a mercury well for holding a body of liquid mercury and connectedat the top with the side of said tube, through a, vertically extendingsubstantially centrallyl located capillary passage. a high frequencycoil for heating and distilling the mercury in said well and means forenabling regulation of such -distillation including a support forlocating and holding said high frequency coi in surrounding relationabout said mercury wel and means i'or timing the mercury distillingeffeci of said high frequency coil.

CHARLES CHIRELSTEIN.

